Question

factor completely
16t^2+49-56t

Answer 1

16t^2+49-56t
= 16t^2-56t+49
= (4t)^2 - 2(4t)(7) + 7^2
= (4t - 7)^2

Basically, we rearrange the terms and apply the identity (a-b)^2 = a^2 - 2ab +b^2 here.
Hope it helps.